Knowing requires thought, and thought requires reason.
Newborn babies find themselves launched into a world of sensual chaos. Even with all their on-board sense mechanisms working, they know nothing as to meaning within those sensual inputs.
Focusing the eyes is a learned function, even listening is a learned function (Please, people, read to your little ones).
Focusing the mind onto sensual inputs requires ... learning, and then ... knowing.
P.S. These thoughts are based on my reading of Ayn Rand's "Introduction to Objectivist Epistemology" -- it is an incredibly impressive book.
I've read almost all of Rand's books. She introduced me to Aristotle and from there I progressed to Aquinas' philosophy.
You might want to contrast her theory with that of Aquinas, but begin with these few paragraphs on the problem of he knower and the thing known.